a. Field of the Invention
This invention is in the field of solderless spade-type electrical connectors, in which a clamping means is used to immobilize a bendable strand or lead to dispose and secure the lead between surfaces urged towards each other to grasp the part therebetween and in which the clamping force is exerted by a resilient blade portion of the connector along one edge in cantilever fashion, the spade type connector being especially useful for immobilizing the moving lead portion of the loudspeaker for connection to the electrical power input terminals. The field of the invention includes the method of joining of an electrical conductor in the form of a bendable or flexible strand or lead to a solderless electrical connector which is of the spade-type of solderless connector.
B. Description of the Prior Art
Heretofore the connection of the flexible moving leads of a loudspeaker to the electrical power input terminals have been accomplished by soldering in an assembly line manufacturing facility. The requirement of the soldering operation is to provide for a low loss electrical and mechanical termination of the flexible moving leads and unrestricted movement of the loudspeaker moving system within its design limitations, the loudspeaker moving system comprising the voice coil, spider, and cone.
The termination of the flexible moving leads must be such that no mechanical slippage in use occurs which could result in subsequent snubbing of the leads in response to the motion of the loudspeaker moving system.
The flexible moving leads must be secured so that conversely slippage could not increase the length which could result in the leads rubbing against some portion of the loudspeaker frame or terminal board or against each other in response to motion of the loudspeaker moving system.
In the prior art of soldering, rising labor costs have been encountered and meticulous inspection is required to insure against defective solder joints and molten solder dropping onto its moving system parts resulting in faulty performance of the loudspeaker. A high degree of skill is needed.
Solderless connectors have not heretofore been proposed for the present use, and the known connectors, such as in Rutter, U.S. Pat. No. 3,065,451, Cobaugh, U.S. Pat. No. 3,191,281, Cobaugh, U.S. Pat. No. 3,239,918, and Cobaugh, U.S. Pat. No. 3,243,757, are not structurally suitable to meet the requirements heretofore met by the soldered connection for the flexible leads of the loudspeaker connection to the power source.
In Rutter, U.S. Pat. No. 3,065,451, the engagement of the flexible lead wire is to a projecting tip which fits into a retaining element. This type of connection (male-female) is unsuitable to the present loudspeaker connection, because there is no provision of the free ends of the leads after immobilizing the portion of the lead connected to the speaker.
Similarly, in the Cobaugh U.S. Pat. Nos. 3,191,281, 3,239,918, and 3,243,757, special retaining channels are provided for crimping a wire, but the action of the clamping part is such as to produce an S-shaped bend at an exposed corner of the connector which permits the free end of the wire or strand to work back and forth, thereby becoming brittle and tend to break.